<template>
  <el-color-picker
    v-model="theme"
    :predefine="['#1492FF', '#1890ff', '#304156','#212121','#11a983', '#13c2c2', '#6959CD', '#f5222d', ]"
    class="theme-picker"
    popper-class="theme-picker-dropdown"
  />
</template>

<script>
import Vue from 'vue';
import {generateTheme} from '../../utils/element-theme';
import {ColorPicker} from "element-ui";

const version = require('element-ui/package.json').version; // element-ui version from node_modules
const ORIGINAL_THEME = '#1492FF'; // default color

Vue.use(ColorPicker);
/**
 * 主题选择
 * @author maolin
 */
export default {
  data () {
    return {
      chalk: '', // content of theme-chalk css
      theme: ''
    };
  },
  computed: {
    defaultTheme () {
      return this.$store.state.settings.theme;
    }
  },
  watch: {
    defaultTheme: {
      handler: function (val, oldVal) {
        this.theme = val;
      },
      immediate: true
    },
    async theme (val) {
      let _this = this;
      const oldVal = this.chalk ? this.theme : ORIGINAL_THEME;
      await generateTheme(val, oldVal, ORIGINAL_THEME, version, this.chalk, function (chalk) {
        _this.chalk = chalk;
      });
      this.$store.dispatch('settings/setGlobalPrimaryColor', val);

      // if (typeof val !== 'string') return
      // const themeCluster = this.getThemeCluster(val.replace('#', ''))
      // const originalCluster = this.getThemeCluster(oldVal.replace('#', ''))
      // console.log(themeCluster, originalCluster)
      //
      // const $message = this.$message({
      //   message: '  Compiling the theme',
      //   customClass: 'theme-message',
      //   type: 'success',
      //   duration: 0,
      //   iconClass: 'el-icon-loading'
      // })
      //
      // const getHandler = (variable, id) => {
      //   return () => {
      //     const originalCluster = this.getThemeCluster(ORIGINAL_THEME.replace('#', ''))
      //     const newStyle = this.updateStyle(this[variable], originalCluster, themeCluster)
      //
      //     let styleTag = document.getElementById(id)
      //     if (!styleTag) {
      //       styleTag = document.createElement('style')
      //       styleTag.setAttribute('id', id)
      //       document.head.appendChild(styleTag)
      //     }
      //     styleTag.innerText = newStyle
      //   }
      // }
      //
      // if (!this.chalk) {
      //   const url = `https://unpkg.com/element-ui@${version}/lib/theme-chalk/index.css`
      //   await this.getCSSString(url, 'chalk')
      // }
      //
      // const chalkHandler = getHandler('chalk', 'chalk-style')
      //
      // chalkHandler()
      //
      // const styles = [].slice.call(document.querySelectorAll('style'))
      //   .filter(style => {
      //     const text = style.innerText
      //     return new RegExp(oldVal, 'i').test(text) && !/Chalk Variables/.test(text)
      //   })
      // styles.forEach(style => {
      //   const { innerText } = style
      //   if (typeof innerText !== 'string') return
      //   style.innerText = this.updateStyle(innerText, originalCluster, themeCluster)
      // })

      this.$emit('change', val);

      // $message.close()
    }
  },

  methods: {
    /**
     * 更新样式
     * @param {string} style 样式
     * @param {array} oldCluster
     * @param {array} newCluster
     * @private
     */
    updateStyle (style, oldCluster, newCluster) {
      let newStyle = style;
      oldCluster.forEach((color, index) => {
        newStyle = newStyle.replace(new RegExp(color, 'ig'), newCluster[index]);
      });
      return newStyle;
    },
    /**
     * 获取对应url中的css文件的字符串
     * @private
     */
    getCSSString (url, variable) {
      return new Promise(resolve => {
        const xhr = new XMLHttpRequest();
        xhr.onreadystatechange = () => {
          if (xhr.readyState === 4 && xhr.status === 200) {
            this[variable] = xhr.responseText.replace(/@font-face{[^}]+}/, '');
            resolve();
          }
        };
        xhr.open('GET', url);
        xhr.send();
      });
    },
    /**
     * 获取16进制的颜色值
     * @private
     */
    getThemeCluster (theme) {
      const tintColor = (color, tint) => {
        let red = parseInt(color.slice(0, 2), 16);
        let green = parseInt(color.slice(2, 4), 16);
        let blue = parseInt(color.slice(4, 6), 16);

        if (tint === 0) { // when primary color is in its rgb space
          return [red, green, blue].join(',');
        } else {
          red += Math.round(tint * (255 - red));
          green += Math.round(tint * (255 - green));
          blue += Math.round(tint * (255 - blue));

          red = red.toString(16);
          green = green.toString(16);
          blue = blue.toString(16);

          return `#${red}${green}${blue}`;
        }
      };

      const shadeColor = (color, shade) => {
        let red = parseInt(color.slice(0, 2), 16);
        let green = parseInt(color.slice(2, 4), 16);
        let blue = parseInt(color.slice(4, 6), 16);

        red = Math.round((1 - shade) * red);
        green = Math.round((1 - shade) * green);
        blue = Math.round((1 - shade) * blue);

        red = red.toString(16);
        green = green.toString(16);
        blue = blue.toString(16);

        return `#${red}${green}${blue}`;
      };

      const clusters = [theme];
      for (let i = 0; i <= 9; i++) {
        clusters.push(tintColor(theme, Number((i / 10).toFixed(2))));
      }
      clusters.push(shadeColor(theme, 0.1));
      return clusters;
    },
    /**
     * 改变当前的主题
     * @private
     */
    changeTheme (theme) {
      this.theme = theme;
    }
  }
};
</script>

<style>
  .theme-message,
  .theme-picker-dropdown {
    z-index: 99999 !important;
  }

  .theme-picker .el-color-picker__trigger {
    height: 26px !important;
    width: 26px !important;
    padding: 2px;
  }

  .theme-picker-dropdown .el-color-dropdown__link-btn {
    display: none;
  }
</style>
